Thread-cutting die



Nov. 24, 1925 3,108

A. J. FRANCE THREAD CUTTING DIE Filed Jan. 12, 1,925 2 Sheets-Sheet 1 Nov. 24 1925,

' 1,563,108 A. J. FRANCE THREAD CUTTING- DIE Filed Jan. 12, 1923 2 Sheets-Sheet 2 Patented New. 24, i925.

UNITED STATES PATENT OFFICE.

ALBERT J. FRANCE, OF DETROIT, MICHIGAN, ASSIGNOR '10 MUBCI-IEY MACHINE AND TOOL GGMPANY, F DETBOET, MICHIGAN, A CORPORATION OF MICHIGAN.

THREAD-CUTTING DIE.

Application filed January 12, 1923. SerialNo. 612,226.

To all whom e't-ma z concern Be it known that I, ALBERT J. FRANCE, a citizen of the United States, and residing at Detroit, in the county of Wayne and State of Michigan, have invented a new and Improved Thread-Cutting Die, of which the following is a specification.

This invention relates to a self-opening thread cutting die which may be manually closed and which will automatically open when a proper instrumentality is actuated in order to permit withdrawal of the work, and its objectis to provide a die of this character with radially movable chasers and springs to press them outward, manually operable means to press the chasers inward, and readily adjustable means for determining the eXact positions of the chasers when in their operating or thread-cutting post tions.

A further object of this invention is to provide a die of this character which can be readily disassembled to permit replacmg of the several parts, which shall have a minimum number of parts, and in which the parts shall all have ample strength.

Another object of this invention is to pro vide a die of this character in which all the manufacturing operations are simple and do not require special machines.

In the accompanying drawings, Fig. 1 is a plan of this improved die. Fig. 2 is a front and Fig. 3 a rear elevation thereof. Fig. 41 is a front elevation of the body with the Chasers in position. Fig. 5 is a rear elevation of the control sleeve. Fig. 6 is a section of the die on the line 6-6 of Fig. 8. Fig. 7 is a side elevation of the body with the chasers in position, a portion of the body being broken away to disclose a chaser and its guide. Fig. 8 is a section on the line 88 of Fig. 6. Fig. 9 is a front elevation of the body without the chasers. Fig. 10 is a perspective of a chaser.

Similar reference characters refer to like parts throughout the several views.

The body 1 of this die is generally cylindrical and has a cylindrical threaded eX- tension 2 to receive the adjusting nut and a further extension 3 which may be called the shank as it is received in the lathe turret or other support for the die. The central hole 1 permits the work to be acted upon by the chasers for any desired distance. The front end of the body is formed with rectangular radial grooves 5 for the chasers 6, and with radial round holes 7 (Fig. 7) for the chaser guides 8 which are hollow cylindrical bodies having outer ends 9 perforated to receive the screws 10 which limit their outward movements. These guides fit over the springs 12 by means of which they are pushed outward.

The grooves 5 and holes 7 connect by means of slots 13 which permit the fingers 14 on the guides 8 to extend into the holes 15 in the chasers 6, so that the springs 12 serve to press the chasers outward. The chasers are held in their grooves by means of the face plate 16 of the front cap, the flange 18 of which extends back over the control sleeve. .Screws 17 may be used to secure the front cap to the bodyand a pin 19 may be used to position this cap before it is se cured by the screws.

The control sleeve 21 is slidable on the body and is generally cylindrical with a co-nicalinner surface 22 at its outer end, the angle of which is the same as the angle of the outer ends 23 of the chasers. This sleeve is moved outward manually and forces the chasers inwardly because of the inclination of their engaging surfaces. The outer diameter of the main portion of the sleeve is preferably the same as that of the flange 18 of the front cap, the end of the sleeve be ing reduced at 24.- to receive this cap. prevents the entrance of dust and gives a good finish to the die.

The sleeve has an internal radial flange 25 against which the small plungers 26 are pressed by the springs 27 seated in longitudinal holes 28 in the body. The action of these springs is to force back the sleeve when released and permit the springs 12 to move the chasers outwardly. The rear end 29 of the shelland the flange 25 and the rear cap 30 which is attached to the end 29 by the screws 82, constitute a chamber for the trip ring 83 (Fig. which has a finger 3a projecting outthrough a notch in the end 29. A spring 36 seated in the notches 37 normally pushes this finger 34 outward.

The adjusting nut 38 (Fig. 6) preferably has a circumferential flange 39 provided with holes 40 to receive a spanner wrench or other tool by means of which it may be turned. It may be secured at any desired position on the part 2 of the head by means of a set screw 42. The end 39 may be graduated, as

This

ill?) shown in Fig. 1, and the ring- 30 may have a pointer 4-3 so that the angular distance the nut is turned may be accurately determined.

In order that this trip ring may be prop erly guided, itiat faces All may he formed thereon and guide hl'ocks may be secured to the inner wall of the end 29 of the sleeve 21 by pins 46. The adjusting" nut extends into the trip ring" 33 and has a cireumfereir tial shoulder ll adapted to be engaged thereby and to receive the thrust of this trip ring and of the control sleeve. When the parts are as shown in Fig. {3 with the chasers forced inward to thread cutting position. the work rotates relative to the Chasers, but it is in'nnaterialwhether the work or the die turns, although in practice the die docs not rotate but moves longitudinally of the work as threads are bein i cut thereon. lVhen the desired length of t .eads have been out, the hi yer 3% is pressed inwardly. which moves that portion of the trip ring 3?) oprmsite the linger out of engagement with the shoulder -17 on the nut- 38.

This movement of the finger 34: is caused in machines where the die rotates v the linger striking a part of or projection on the work support wl'rich moves toward the die with the work. hen the rotates and the die moves to "aid the work. an arm on the work support engages the lin er 34 when the thread being; cutis of su'ni-cient length. It will be noticed that the external diameter of this shoulder 4-7 is slightly less than the internal diameter of this trip ring so that when these two parts are concentric. the collar can freely slide hack on the nut under pressure of the spring 27. This releases the pressure of the inclined surface 22 of the control sleeve on the ends 23 of the chasers and permits the springs 12 to move the chasers outward.

lVhen the work and (lie have been moved apart the chasers are forced inward by merely moving the sleeve 21 outward until the trip ring 33' slips o ll the shoulder 47 of the nut and is then held in its eccentric position by the spring 36.

It will be seen that the exact operative position of the sleeve 21 longitudinally of the body is fixed by the shoulder 4-7 of the adjusting nut. and as the position of the sleeve and its conical surface 22 determines the positions of the ehasers, the working positions of the chasers are determined by the nut 38. The depth of the threads can therefore he accurately determined by this adjusting nut. If desired, a groove 4?) may he formed in the body and a screw 50 mounted in the sleeve to extend into this groove to prevent the sleeve from turning: on the body.

All of the different parts of this die may he machine finished as all the parts are simple and of ample strength. lVhen the screws are removed the die may be entirely disassembled. Chasers may be replaced, by simply ren'ioving the screws l? and the cap. The. forward D'lOVeiDQHt of the sleeve 21 is limited by the front cap and its rearward movement by the shoulder 39 on the nut.

The details and proportions of this die may all he aried by those skilled in the artwithout departing from the spirit of my invention as set forth in the following claims.

I claim 2- l. A die comprising a eylindneal body having radial. grooves in its forward end, spring pressed ehasers slidalole in the grooves a cap to keep the chasers in the grooves a spring pressed sleeve slidahle on the body and having a circumferential inclined surface engaging the chasers and adapted to move them inward when the sleeve is moved forward a: nut adjustahly mounted on the body and having a shoulder to determine the operative position of the sleeve and of the chasers, a trip ring carried by the sleeve and adapted to lie in front of said. shoulder to hold the sleeve forward, and a spring to hold the trip ring in front. of said shoulder.

2. A. die comprising a cylindrical body having radial grooves in its forward end, spring pressed Chasers slidable in the grooves, a spring pressed sleeve slidahle on the body and having a cirruinferential in clined surface engaging the chasers and adapted to move them inward when the sleeve is moved forward. a nut adjustahly mounted on the body and having a shoulder to determine the operative position of the sleeve and of the Chasers, a trip ring carried by the sleeve and adapted tolie in front of said shoulder to holdthe sleeve forwai-'d a spring to hold the trip ring in front of the shoulder. and spring actuated pluuo'ers mounted in the body to force the sleeve back when the trip ring is released from said shoulder.

3. A die comprising a eylimlrical body having-radial grooves in its forward end and radial holes adjacent the grooves, chascrs slidable in said grooves. 'uidcs slidahle in the holes and connecting to the chascrs springs mounted in the holes to press out the guides and chasers. a spring pressed sleeve slidable on the body and having a circumferential inclined surface contacting with the outer ends of the Chasers and adapted to press them inwardly when the sleeve is moved forward, spring pressed plungers mounted in the body and adapted to press the sleeve rearward. an adjustable member mounted on the body and havingan engaging surface, and a spring pressed ring mounted on the sleeve and adapted to contact with said engaging surface to hold the sleeve in its forward position against the pressure of the plungers.

ALBERT .l. FRANCE Inn 

